Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 151, NWS Des Moines, IA

August 8, 2012Greene County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Aug 8, 2012, 2:37 PM CDT for Greene County, Iowa. It was in force for 53 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 8, 2012, 2:37 PM CDT (19:37 UTC)
Expired: Aug 8, 2012, 3:30 PM CDT
In force: 53 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.5 in
Wind: 60.0 mph

County Greene County, IA

The radar

The Des Moines radar (KDMX), 65 km from the middle of the area, began a volume at 19:38 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Aug 8, 2:39 PM CDT	HAIL 1	Scranton, IA

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 8, 2:21 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 7.6 hours before the alert went out and 187 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 994 J/kg
Mixed-layer CIN: -254 J/kg
Mixed-layer LCL: 1661 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 103 m²/s²
0-3 km storm-relative helicity: 78 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

042 
WUUS53 KDMX 081937
SVRDMX
IAC073-082030-
/O.NEW.KDMX.SV.W.0151.120808T1937Z-120808T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
237 PM CDT WED AUG 8 2012

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  GREENE COUNTY IN WEST CENTRAL IOWA...

* UNTIL 330 PM CDT

* AT 234 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING PING PONG BALL SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
  LOCATED 8 MILES SOUTHEAST OF GLIDDEN...OR 15 MILES EAST OF
  CARROLL...AND MOVING EAST AT 20 MPH.

* LOCATIONS IMPACTED INCLUDE...
  JEFFERSON...GRAND JUNCTION...DANA AND PATON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOVE TO AN INTERIOR ROOM AND STAY AWAY FROM WINDOWS. IF YOU ARE IN A
MOBILE HOME...GET OUT NOW...AND SEEK SHELTER IN A REINFORCED
BUILDING.

&&

LAT...LON 4221 9419 4197 9416 4191 9463 4205 9463
TIME...MOT...LOC 1938Z 258DEG 19KT 4201 9455
WIND...HAIL 60MPH 1.50IN

$$

2 follow-up statements

910 
WWUS53 KDMX 082003
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
303 PM CDT WED AUG 8 2012

IAC073-082030-
/O.CON.KDMX.SV.W.0151.000000T0000Z-120808T2030Z/
GREENE IA-
303 PM CDT WED AUG 8 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR GREENE COUNTY
UNTIL 330 PM CDT...

AT 259 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
JEFFERSON...OR 24 MILES EAST OF CARROLL...MOVING EAST AT 20 MPH.

LOCATIONS IMPACTED INCLUDE...
  GRAND JUNCTION...DANA AND PATON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE FOR LARGE HAIL...DAMAGING WINDS AND DEADLY CLOUD TO GROUND
LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...PREFERABLY
INSIDE A REINFORCED BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 4221 9419 4200 9416 4197 9417 4194 9443
      4207 9454
TIME...MOT...LOC 2003Z 258DEG 19KT 4204 9438
WIND...HAIL 60MPH 1.00IN

$$

437 
WWUS53 KDMX 082021
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
321 PM CDT WED AUG 8 2012

IAC073-082031-
/O.EXP.KDMX.SV.W.0151.000000T0000Z-120808T2030Z/
GREENE IA-
321 PM CDT WED AUG 8 2012

...THE SEVERE THUNDERSTORM WARNING FOR GREENE COUNTY WILL EXPIRE AT
330 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
 HOWEVER SMALL HAIL AND GUSTY WINDS ARE STILL POSSIBLE WITH THIS
THUNDERSTORM.

LAT...LON 4221 9419 4200 9416 4197 9417 4194 9443
      4207 9454
TIME...MOT...LOC 2021Z 258DEG 19KT 4206 9425

$$

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 7, 7:45 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Cass	45 min
Aug 8, 2:00 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Carroll, Greene	45 min
Aug 8, 3:01 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Dallas, Greene, Guthrie	43 min
Aug 8, 3:09 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Madison	51 min
Aug 8, 3:30 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Story	30 min
Aug 8, 3:54 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Polk	38 min
Aug 8, 4:16 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marion, Polk, Warren	29 min
Aug 8, 4:45 PM CDT	Severe Thunderstorm Warning	DMX	Hancock, Winnebago	36 min
Aug 8, 4:48 PM CDT	Severe Thunderstorm Warning	DMX	Worth	27 min
Aug 8, 6:05 PM CDT	Severe Thunderstorm Warning	DMX	Butler, Cerro Gordo, Franklin	25 min
Aug 8, 6:29 PM CDT	Severe Thunderstorm Warning	DMX	Butler, Franklin	46 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2012 Every severe thunderstorm warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.